It wraps around the animal's neck and mid-section and is secured in place with Velcro straps.

The wrap creates pressure without restricting the dog's movement.

"Pressure has a calming effect on the nervous system," the site says. "Using pressure to relieve anxiety has been a common practice for years."

"That's like a giant, wearable hug that never ends," says the site's promotional video.

"Probably the toughest dog to train is a dog that's afraid of the world," says Scott MacConachie, a certified dog trainer and owner of K9 Ponderosa in Delaware, Ohio.

MacConachie says our pets are just "designer wolves" that have the same pack mentality as their undomesticated cousins.
He often uses his own pack of "balanced dogs" to help heal issues with problem pooches.

His own dogs are trained to flip light switches and even retrieve the mail from a closed mailbox.

NBC's Columbus, Ohio affiliate WCMH took the Thundershirt to him for a few tests.

"I think it has some validity. Dogs do like compression," MacConachie says. "But I don't think it's going to cure a dog that's fearful of the world or a dog that has real fear or anxiety issues."

As MacConachie gave commands to Winnie in the K9 Ponderosa facility, the dog seemed to understand, but was too nervous to stay in a sit or down position.

He would bounce up and down, unable to stay still or concentrate.

When told to walk or heel, Winnie would break into a near run.

Then he was strapped into a Thundershirt.

The straps needed to be adjusted a few times to give his troubled shoulder some support, but MacConachie Bechtel noticed an immediate change in his behavior.

Almost instantly, the dog was less anxious and he was able to concentrate.

"This is different," noticed MacConachie with a bit of surprise. "And now, he is listening and he is doing the commands and he is being more patient."

The dog stayed in a sit position.

He stayed in a down position.

He walked more slowly and confidently.

"I'm seeing a very calm dog compared to when we first walked in," said Susan once Winnie was sitting on her lap again. The dog was nearly falling asleep in her arms. That never happened before the Thundershirt.

Drake was then strapped into a large-sized Thundershirt.

Like Winnie, his behavior and demeanor changed almost instantly.

When another knock came at the door, Drake slowly wandered over to the door without barking, and then turned and walked away as the other dogs continued barking.

"That is amazing. That is unbelievable," remarked Susan. "He's not spinning."

"He's not even barking or jumping," noted MacConachie.

When asked if, in his experience, if it was unusual for a dog's behavior change so quickly, MacConachie said it was.

Sort of.

"It's unusual, yes," he said. "I'm not going to say that it's going to change the world, but it definitely made a difference."

Every dog's situation and psyche is different.

They are as individual as humans, and not every solution works for every animal.